Tools, Trust Center, Add-Ins. On the bottom of that dialog, you see a
combobox with a Go button next to it. Choose the category of add-in you
want to disable (e.g. Com add-ins) and press Go. That will bring up a
dialog where you can disable any com add-in.
I know it's a bit confusing. Every time I open that dialog (and I do
that several times a day) I try to double-click on an add-in name.
Patrick Schmid